The present invention is directed to a process for generating spatiotemporal patterns in a chemical reaction and the device for producing the patterns. In particular, the present invention is directed to a process and device for the creation of spatiotemporal patterns by the uniform feeding of the materials into a reactor in a manner so that convective motion does not interfere with the chemical pattern achieved during the reaction. The process and reactor of the present invention has specific utility in the study of various spatial patterns of chemical reactions to understand the particular mechanism of the reaction and also as a means for concentrating highly desirable chemical intermediates in a specific area of the solution so that these highly desirable chemical materials may be extracted in greater concentrations. Specifically, the process and apparatus may be utilized in biological methods wherein small amounts of highly valuable enzymes are produced and are difficult to separate because of their low concentration.
In the discussion of the process and apparatus of the present invention, specific reference will be made to the Belousov-Zhabotinsky (BZ) reaction system which has been studied for a number of years in an attempt to understand the formation of chemical spatial structures (mainly chemical waves) formed in a chemical reaction. For a detailed description of that work see Vidal et al., "Etude . . . Oscillant", J. Physique, 47, pp. 1999-2009, November 1986, herein incorporated by reference.
Many experiments on spatial self organization in chemical systems have yielded spiral waves and concentric ring patterns. Those experiments were conducted in closed reactors. Hence, the systems evolved irreversibly and uncontrollably toward thermodynamic equilibrium. The transient nature of the spatial patterns and the lack of a well-defined control parameter complicates the interpretation of these experiments and existing theories concerning the asymptotic (long time) states. About a decade ago, the CSTR (continuous flow stirred tank reactor) replaced closed reactors in experiments on well mixed oscillating chemical reactions. Subsequently a wide variety of new dynamical phenomena were discovered in the study of these oscillating chemical reactions.
The present invention is directed to a continuously fed unstirred reactor which can serve as a tool for the systematic study of the spatial patterns generated in these oscillating chemical reactions. The continuously fed unstirred reactor of the present invention (CFUR) can be maintained indefinitely at a fixed distance away from equilibrium by the continuous feed of the chemical reagents. The advantage of the CFUR of the present invention is that a porous medium, in the present embodiment a polymeric gel, prevents the occurrence of convective motion in the reaction. Convective motion has plagued previous studies of pattern formation in chemical reactions. A second advantage of the CFUR of the present invention is the use of a capillary array plate to achieve a uniform feed of the gel layer and a decoupling from the turbulent flow in the mixing chamber.